Automatic telephone system



April 13, 1926.

AUTOMATI C TELEPHONE SYSTEM Filed March 25. 1918 2 sheets-she@ 1 MAT.

1,580,252 E. JAcoBsEN "April 13, 192s.

E. JAcoBsEN AUTOMATIC TELEPHONE SYSTEM Filed March 2.5, 191s 2 sheets-sheet 2 EmMJ/DUDEEU desired to have Patented Apr. 13, 1926.

EMIL JACOBSEN, 0F CHICAGO, ILLINOIS,

ASSIGNOR' T0 AUTOMATIC ELECTRIC I1\`|'C.,OFv

CHICAGO, ILLINOIS,'A CORPORATION OF DELAWARE.

` ATOMATIC TELEPHONE SYSTEM."

Ap131icau0n7 lfi1ed March 25, 191s. seriaiNo. 224,430.

To all whom it may concern.'

Be it known lthat I, Eirin ,Jncosrm a vcitizen of theUnited States of America, and a residentV of Chicago, Cook Countyand State of Illinois, have invented certainnew and useful Improvements in Automatic Telephone Systems, of' which the tollowingis a speciiication. Y Y y' p My invention relates in general toL automatic telephone systems and v I have` applied the same toa ksystem in whichvautomatic selector switches of theStro'wger type are used orthe purpose of automatically selecting an idle trunk line.

In ysystems of thisV character it hasbeen the practice in thel past to use a selector switch of the standard type having ten. levelsA of contacts ot .ten eachy which may be selected by the selector; that is, whenfone digit is dialedv tolselect the level. or group desired, the yswitch automatically rotates to pick out one ofthe ten trunks in that group. It is very' often desirable, however, to split up the groups; that is, it might be tour trunks of one level v leading to onelbranch exchange and the Vother rsix trunks. extending to another exchange. lIn this casemeans must be provided to determine which group ofv trunk lines the switch will bedirected to', the irst tour or the last six.

t isan object of my invention to provide a switch which isarranged yto accomplish. this result andwhich vat the will of the calling subscriber may be operated to select trunks in either of two groups in one level.

In the drawings comprising Figs; 1. and 2 I have shown a calling` substation A (Fig. 1) having access to selector switches E through the medium of the well known rotary type of line switch C; Thek selector E is of the wellv known Strowger type similar to that shown. in U. S. LettersPatent T-l-tlQi, granted March 13, 1906, to Keith, Erickson, and Erickson, except. that the' side switch has been yomitted and thecircuit has been rearranged to,` operatev overV *twoy sides of a calling linein series. p

Accessiblev` tothe selectors nurnber of similar selectors suchasD, r(FiggQ) Y the circuit of which has been improved to adapt it to operate in accordance with my invention. This selector D is made accessible to the selector E through two different levels of the banket saidselector E. ,Each

. contactsv of the next trunk line.

level of the banks of theselector D may be divided intotwo groups of any desired number, each group leading to a different branch exchange.` It the selector D is seized by the selector E yat'oney level of thebank it willr operate to select trunks onlyin the lirsty group, while if it is seized romfthe other, level it will operate toselect trunks only in the last group. I .v f

I will now describe 'the' operation of the switches` inydetail whena c-all' is made Y the subscriber; A;

Then the.,subscriber at substation removeshis receiver, a circuit is,y closedat the, switchholok-'springs for .the line relay 2 of switch C'inseri'eswith the line circuit. Re-v lay 2 energizes to close apcircuit at springs SQ including. the ,switchingv relay' 3 andy rotarymagnet 4 in series and at the Sametime to close la circuit at springs 9 lfor the magnet 4 to the private wiper 7. Now it will be understood that iflthe trunk line upon which the switch C isrestingis busy and aground iswffpresent o n the4 private contact thereof, this ground will short circuit-the high refy sol sistance relay v3 andenergize the rotary mag-`r net 4; tostep the wipers' 5, Gand 7 to the It theV next trunk. line iS-busy, this voperation will con-A tinue until an idle trunk is reached, at which time 'there will be no ground present at the contact which wiper 7 meets. Relay 3 will be nov longer short circuited, therefore and will immediately energize over the series circuit aboveV traced, to disconnect the relay 2 and extend said line circuit to the trunk 'leadingto selector E by means of the ysprings 10 andll.A f Y' As soon as relay '3 energizes a circuitk is closed, 'for the linev relay 12 of switch Ein series `with the line circuit and wipers Band 6.` Relay 12,' upon energizing, closes a circuity for .slow release relayl 13'. Relay 13 ener'gi'zes to prepare a circuit at springs 14 and 15 for the series relay 17 and vertical ymagnet 18, opens a point Airrthefcircuitfof the release magnet 19 at springs 1 4. and1'16, andvclosesma;circuitb at springs 2() lto hold fthe' relay 3v of switch-C energized'.

As' soon asy the 'iirst digit of rthe calledV number isV delivered by the calling device CD, the relay 12 operates tov open and close the vcircuitbf magnet 1S.` to thereby step the wir-piers... 2.1, and; 23ste@ desir/@4t level '0i ground from the line circuit'and f the banks. Relay 1T also energizes in se ries With magnetl 1S and operates to close a circuit tor rotary interrupter relay 24 at springs and 26. Relay 24 energizes to prepare ay circuit for the rotary magnet at springs 30 and also closes a lockingcircuit for itselt' through springs 27. As soon as relay 17 deencrgizes, the circuit ot the rotary magnet 28 is closed at springs 25 and Magnet 28 there'tore operates to rotate the Wipers onto the iirst contact otl the elected level and opens 'the locking' circuit ot relay 24 at springs 3l. Relay 24 then deenergizes and again opens the circuit ot magnet 28 at springs 30, which magnet deenereizes to prepare a new circuit tor relay 24 to the private. Wiper 23. It the tiret. trunk is busy, the relay 24 will again be energized to cause magnet 28- to step the Wipers to the ne \:t trunk. lli/Then the iirstidle trunk is reached, no ground is present at Wiper 23 and relay 32, which has heretotore been short circuited, is energized in series with relay 24 from ground at springs 20. Relay 24, being of comparatively low resistance, does not energize at this time. RelayV upon energizing, extends the line circuitl ot substation n. to line Wipers 21 and 22 and prepa-res a lockingv circuit tor itself which Will be completed over Wiper 23 from the nextsucceeding switch.

Assuming that the Wipe 21, 22, and 23Were raised opposite the first ot the two levels in 'which terminated the trunk line 'leading to selector switch D (Fig. 2), and selected contacts and then as soon as relay 32 energizes, a circuit closed tor the line relay 3d ot the-selector switch i) in series with the line circuit and Wipers 21 and 22. Relay 3G energizes to close a circuit tor release relay Si' which in turn energizes to prepare a circuit for the vertical maegnet 33 and sloiv rela-y 39 and also connects `@round to the release trunk through springs 4t). rlfliis ground on the release trunk makes the selector D busy at contacts 34 and 45% and their multiples and also supplies a. holdingground tor relays 3 and 32 ot switches C and E, respectively.

The calling device CD is now operated for the second digit o't the called number, the impulses of which digit operate relay to in turn operate the vertical magnet 3Sv to raise the wipers 4.4, 45, 48, and 47 to a desired level ot the bank. l have shown one lei'el ol" contacts in the baul: as divided into tivo groups, the lirstl live con-v tacts being,` connected to trunk lines leading' to one exchange and the last tive contacts being' connected to trunk lines leading' to another exchange. The calling subscriber has already determined that he desires to select trunks in the second group (the last 5 contacts) by seizinO' the selector D troni the lower level (contacts 33 34 and 35,)

, u l 7 l 'lhereto e, when the impulses tor the second digit cease, the relay 39 Will dcenergize and close a circuit tor rotary magnet 48, which `has been pre-pared by relay 49, in the same manner as explained in connection with the selector E. hiag'net 48 operates to rotate the Wipers onto the iirst set ot contacts 5() to 53, inclusive. lt will be noted that the upper contact ot each pair ot contacts associated with the iii-.st group ot tive trunks is grounded, so that when the magnet 48 deenergizes after its lirst operation, al circuit Will be closed for the relay 49 extending from ground through contact 52, Wiper 46, springs 54 anc 55, springs 56 and 57, springs 58, springs 59, and rela-y 49 to battery. Relay 49 therefore energizes again to again close a circuit for. the magnet 48, which magnet Will rotate the Wipers to the. second contact and again open the circuit ot relay 49. This alternate operatiorL ot' relay 49 and magnet 48 causes the Wipers to be rotated rapidly to the iirst set ot contacts in the second group, in this instance, the sixth Contact. From this point the upper contacts ot the bank are connected in the usual manner to the release trunks ot' other selectors or connectors so that the automatic rotation ot the selector depends upon the busy or idle condition of said trunks and when the Wipers reach one ot said trunks which is idle, the switching relay 60 is energized in the saine manner as relay 32 of selector E to switch the extended connection through to the selected trunk.

Assumingnov.7 that the calling subscriber desires to select .trunks in the tirst group, that is, one ofthe first 5 contacts, the selector E will be operated to select the selector l), or a similar selector, from another level, one set ot contacts in said level being' shown at 4l, 42, and 43. When these contacts are seized, a circuit vill be closed tor the line relay 36 ot the selector D in the same manner as When the switch was seized over the iirst level except. that this circuit Will include a winding ot a special relay 6l. Relay (il Will therefore operate in series With the line relay 36 and lock itself to ground through the springs 40 of release relay 37. Relay 6l also operates to short out the lower Winding from the line circuit and to switch the testing circuit 'from the private Wiper 4G to the private Wiper 47, The line relay 36 is operated in the'inanner hereinbeto-re described to control the vertical magnet 3S to step the wipers to the desiredlevel, and to control relay 39 to cause the Wipers to be stepped on to the first contactl of the group by .means ot' rotary magnet 48. lt will be noted that at this time the ground, which is permanently connected to vthe upper private contacts ot the .first group,has no eitect on the switch, as the circuit from the upper private Wiper is open at springs 54 and 55,

As soon as the; rotary" magnet falls back after4 its initial eiiergization, the circuitfor' operating the relay i9 againwill extend `from contact 53, through wiper 47, springs 62 and 55, springs. 56y and 57, springs' 58,- springs '59', and said relay'to battery. If this contact is busy,rclay i9 will operate in the usual man;

ner to step theswitch tothe second contact of the group and so on until an' idle trunk line` is reached, at which time relay 60 will be energized to switch the connection through to the seized trunk line. Should all the trunk lines of the iirst group of contacts be busy, the switch will rotate onto the sixth contact which terminates o-ne of the trunks of the Vsecondvgroup and is notl accessible forV this call. The switch willthen berotated on past thel lastv contact without stopping' duev to the ground permanently connected to the lower contacts of each set. Assuming that' an idle trunk is selected, however, the

connection may be extended through other switches to a Called subscriber and` aftercori--` versation is completed, may kbe released in the manner peculiar to switches of this type.

It will be seen, therefore, that I have provided an improved mechanism and circuits therefor which makes it possible' to divide the levels of a selector switch into smaller I my invention,

lines accessible thereto, means for making certain of said trunks busy when in use, a pair of test wipers for theswitch, and means involving the use of one of said wipers for preventing the switch from seizing the trunks of one group even though not in use` and involving the use of the other wiper for' enabling the switch to select an idle,y

trunk in said group.

2. In a telephone system, an automatic'.

trunk selecting switch, two groups of trunk lines Aaccessible thereto, a pair of testwipei's for the switch, and means involving the use of one of said wipers for prevei'itingl the v switch 'from seizing the trunks ofone group,

and involving the use ofthe otherwiper for enabling the switch to select an idle trunk in said group, said wipers being used in the reverse order` for the same purpose when testing trunks'in thev other group'. y i

In a telephone' system, an automatic trunk selecting switch, a plurality of groups of, trunk lines accessible thereto, a pair of test wipers for the switch, means for making each group of trunks artificially busy to a ltain ofsaid wipers, means involving diflerent'- one yof said wipers,- n ieans involv-y l ing tlieiuse of one of said test wipers for prie- `i3' cnting the s-iifitch from selectii'igidle trunk lines in the group which is artificially'busy thereto andA involving the other test wiper for preventing theswitcli Jfrom selecting idle trunk lines in another of said groups;

v4. In a 4telephone system, an automatic trunk selecting switch, a plurality of groups of trunk lines accessiblethereto, avpairv of testwipers therefor,=means for making certain ofV said groups artificially busy to cerof one of said vtest wipers for causing` the switch Vto. select idle trunks in only the groups which are not artiticiallyibusy thereto and involving the other of said'test wipers for causing theswitch to'select idleftrunks in only the rest of said groups. Y

' In a'V t'e'l phone system, 'an automatic trunk selecting' switch, a plurality of groups the use ot trunk lines accessible .t'hereto,a pair of f' test wipers for the switch, means involving the use of one of said test wipers forpreventing :the switch from selecting trunk lines in certain of said groups and 'involving the other Vtest wiper for preventing the switch from yselecting trunk lin-es in the remainderof said groups, the first mentioned testwiper controlling the selection of an idle trunk in any of the last mentioned groups andthe last mentioned test wiper ccontrolling the selection of an idle trunk vin any of ,the first' mentionedr groups.

V16.111' a telephone system,V` an automatic trunk selecting switch, two groups of trunk lines accessible thereto, a pair of test wipers for the switch, means involving the use of one of. said wipers tor preventingthe switch 1 from seizing the trunks of one group, and

involving the use of the other wiper forenabling the switch to select an idle trunk in said group, a pair ot trunk lines terminating in said switch and over which said' switch may be seizedland automatic meansfcontrolled by the seizure of the switch over one 4ofsaid last mentioned trunk lines for'rendeii'i'ig one of said wipers ineffective and controlled bythe seizure of the switch 4over ,the other trunk line of v the pair to render the other wiper-ineffective.

" 7. In al telephone system, lan automatic tii'inkselectiiig switch, a' lplurality of groups' of trunk lines accessible thereto, a pair. of

test" wipers for the switch, meansv involving the use otone'of saidytest Awipers forl preventingthe switch from selectingltrunk lines vin certain off' said groups and involving the other test wiper forv preventing the switch from selecting trunk linesv in the remainder of said groups, a pair of paths over which said switch may be seized, and automatic means operated when thefswitch is seizedy over one path forbriiiging the switchunder the exclusive control of one of said test wipers and operated when th-e switch is seized over the other path for bringing the switch under the exclusive control of the other wiper.

8. In a telephone system, an automatic trunk selecting switch, a plurality of groups of trunk lines accessible thereto, a pair of test wipers therefor, means involving the use et one of said test wipers for causing the switch to select trunks in only certain ot said groups and involving the other of said test wipers for causing the switch to select trunks in only the rest of said groups, a pair of paths ovler which said switch may be seized, and automatic means which operates in one manner when the switch is seized over one path to cause only one wiper to control the switch in its trunk selecting movement and in another manner when seized over the other path to cause only the other wiper to control the switch.

9.111 a telephonie system, an automatic trunk selecting switch, two groups of trunk lines accessible thereto, each ot said groups or trunks having a set ot test contacts normally busy and another set normally non busy, a pair of test wipers for the switch ach having access to the normally busy contacts of one group and the normally non busy contacts of the other group, and automatic means operated when the switch is seized io-r predetermining the wiper which is to be used to test trunks and therefore the group in which a trunk is to be selected.

10. ln a telephone system, an automatic trunk selecting switch, two groups of trunk lines accessible thereto, each otsaid groups of trunks having a set of test contacts normally busy and another set normally non busy, a pair of test wipers for the switch each having access to the normally busy contacts ot' one group and the normally non busy contacts oi' the other group, a pair of trunk lines over which the switch may be seized, and automatic means operated when the switch is seized over one trunk line for causing only one wiper to control the switch and operated when the switch is seized over the other trunk for causing only the other wiper to control the switch.

11. In a telephone system, an automatic l trunk selecting switch, two groups of trunk lines accessible thereto, a pair of test wipers i'or the switch, means involving the use ot one ci' said wipers for preventing the switch from seizing the trunks of one group, and involving the use oit the other wiper for enabling' the switch to select an idle trunk in said group, testing means associated with said wipers, a relay for switching the testing means from one wiper to the other, said rclay operated automatically when the switch is seized in one manner to render the testing means subject to only one wiper, and remaining normal when the switch is seized in another mann-er to render the testing means subject to only the other wiper.

12. In a telephone system, an automatic switch, a pair of wipers therefor, two groups of trunl; lines having test contacts accessible to said wipers, means controlled by the manner ot seizure oi the switch for predetermining one of said wipers for use, the wiper thus predetermined controlling the switch to prevent seizure of idle trunk lines in one group and to permit seizure of an idle trunk line in the other group.

13, In a telephone system, an automatic switch, test wipers therefor, trunk lines ac.- cessible to said switch each having a pair ot' test contacts, means for making one of the contacts in each or' said pairs always artilicially busy, means for seizing said switch, and means for causing said switch to be controlled over one test wiper andsaid artificially busy contacts to pass idle trunk lines, or tor causing the switch to be controlled orer another test wiper and the other test contacts of the trunk lines to select an idle trunk.

14. In a telephone system, an automatic switch, trunk lines accessible thereto, test contacts for said switch normally grounded, test contacts for said switch normally onen. means for operating said switch to cause it to rotate over said test contacts, means controlled by said normally groundedfcontact-s for preventing said switch from stopping` on any ci" said test contacts and means for removing said switch from control of said normally grounded contacts and for causing it to stop on one of said contacts.

15. In a telephone system, an automatic switch, trunk lines accessible to said switch, a pair of test contacts for each of said trunk lines, one of each pair being normally grounded, a pair of test wipers for said switch, means for ope 1rating said switch to rotate said wipers over said test contacts, automatic means in said switch controlled by said grounded contacts for preventing said switch from stopping on any of said contacts, and automatic means for rendering said second means inoperative to prevent said switch from stopping.

16. In a telephone system, an automatic switch, trunk lines accessible to said switch, a pair ot test contacts for each trunk line, one of said contacts being permanently grounded and the other being normally open, a test mechanism for said switch, test wipers for said switch, means for operating said switch to rotate said test wipers over said test contacts, and test mechanism normally controlled by said grounded contacts through one of said wipers to continue the operation ot' said switch, and automatic means for disconnecting said test mechanism from said grounded contacts and connecting it with said normally open contacts through said other wiper.

17.7In a telephone system, an automatic switch, trunk lines accessible thereto, a pair of test contacts for each trunk line, one contact ot' each pair being permanently grounded, test mechanism for said switchmeans for operating said switch to test said trunk lines by associating said test mechanism with said test contacts, and means whereby said test mechanism is associated with the normally grounded contacts of certain trunk lines and with the othercontact of the pair on other trunk lines.

1S. In a telephone systennan automatic switch, two groups ot' trunk lines, a permanently grounded contact 'for each trunk in each group, a test contact for each trunk 'in each group, a test wiper for each group having access to the test contacts of its own group and the grounded contacts ofthe other group, means controlled by the engagement of the wiper of the second group with the grounded contacts of the other group for causing said switch Vto move said wipers to the second group, and mea-ns controlled by the engagement of the wiper of the first group with the grounded contacts of said second group for preventing the switch from seizing a trunk of said second group.

19. In a telephone system, a trunk line having two branches at the incoming end, an

automatic vswitch in which saidl trunk ter-y minates at the outgoing end, two groups of lines accessible to Said switch correspond ing, respectively, to said two branches, automatic switching mechanism for extending a call tothe trunk via. either of said branches, Y means for then operating said switch toy further extend the call by way of an idle one of said lines, and discriminating means for causing said switch Vto select an idle line in the particular group which corresponds to theincoming branch in use. Y

20. In a telephone system, a trunk line having two branches at the incoming end, an automatic switch in which said trunk terminates at the outgoing end, two` groups of lines accessible to said switch corresponding, respectively, to said two branches, automatic switching mechanism lorqextending a call to the trunk via either of said branches,

means for then operating said switch to further extend the call by way of an idle one of said lines, testing means in said switch, and means associated with said incoming branches ior controlling the action of said testing .means to cause the said switch to select an idle line in the particular group which corresponds to the incoming branch in use. l Y

21.l In a telephone system, a trunk line having two branches at the incoming end, an automatic switch in which said trunk ter'- minates atthe outgoing end, two groups of lines accessible to said switch corresponding,'respectively, to said two branches, automatic switching mechanism or extending av call to the trunk via either of said branches,

means for then operating said switch to fur- .ther extend the call byl way `of an idle one of said lines, testing means in said switch normally effective to cause said switch to select an idle line in a particular one of said groups corresponding to ajparticular incoming branch, and means responsive in case the call is received over the other incoming i branch for causing said switch to select an idle line in the other group.

22. In a telephone system, fa trunk line having two branches at the incoming end,

an automatic switch in which said trunk terminates at thel outgoing end, two vgroups voilinesaccessible to said switch correspond-A ing, respectively, to said two branches, automatic switching mechanism for 'extending av call to the trunk via either of said branches,

means for then operating said switch to further extend the call by way of an idle onel of said lines, testing means in said switch for Y causing the selection of an idle line in a particular one of said groups, other testing Y vmeans in said switch for causing the selection ofl an idle line in the other group, and meansV for automatically rendering effective only the testing means which is associated with the group corresponding to the incoining branch in use.

' Signed by ine-at Chicago, Cook County,

Illinois, this 21st day of March, 1918.

EMIL JacoBsEN. f

DISCLAIMER.

1,580,252-Em1z't Jacobsen, Chicago, Ill. AUTOMATIC TELEPHONE SYSTEM. Patent dated April 18, 1926. Disclaimer tiled May 12, 1927, by the assignee, Automatic Electric Inc.

Hereby enters this disclaimer to that part of the .claims in said specification which is in the following words, to wit: y l

19. In a telephone system, a trunk line having two branches at the incoming end, an automatic switch in which said trunk terminates at the outgoing end, two groups of lines yaccessible to said switch corresponding, respectively, to said two branches, automatic switching mechanism for extending a call to the trunk via either ot said branches, means for then operating' said switch to further extend the call by way ot' an idle one of said lines, and discriminating means for causing said switch to select an idle line in the particular group which corresponds to the incoming branch in use.

20. In a telephone system, a trunk line having two branches at the incoming end, an automatic switch in which said trunk terminates at the outgoing end, two groups of lines accessible to said switch corresponding, respectively, to said two branches, automatic switching mechanism for extending a call to the trunk via either ot' said branches, means for then operating said switch to further extend the call by way ot' an idle one of said lines, testing means in said switch, and means associated with said incoming branches for controlling the action of said testing means to cause the said switch to select an idle line in the particular group which corresponds to the incoming branch in use.

21. In a telephone system, a trunk line having two branches at the incoming end, an automatic switch in which said trunk terminates at the outgoing end, two

groups ot lines accessible to said switch corresponding', respectively, to said two branches, automatic switching mechanism for extending a call to the trunk via either of said branches, means for then operating said switch to further extend the call 'by way of an idle one of said lines, testing means in said switch normally effective to cause said switch to select an idle line in a particular one of said groups corresponding to a particular incoming branch, and means responsive in case the call is received over the other incoming branch for causing said switch to select an idle line in the other group. 4

22. In a telephone system, a trunk line having two branches at the incoming end, an automatic switch in which said trunk terminates at the outgoing end, two groups of lines, accessible to said switch corresponding, respectively, to said two branches, automatic switching mechanism for extending a call to the trunk via 'either ot' said branches, means for then operating said switch to further extend the call by way of an idle one of said lines, testing means: in said switch for causing Athe selection of an idle line in a particular one of said groups, other testing means in said switch for causing the lselection of an idle line in the other group, and means tor automatically rendering effective only the testing means which is associated with the group corresponding to the incoming branch in use.77

[ytctat Gazette May 3l, 1927.] 

